By papal decree, people younger than 40 could not serve as members of the Inquisition. However, a chain of disasters that struck the world in the 14th century repeatedly led to violations of even the strictest prohibitions.
Vivien Colera and his friend Renar Ciron, novices of a Dominican monastery near the city of Rouen, choose the head of the local Inquisition branch as their assistant. One day, Eliza—a forest hermit—ends up in a Rouen prison under suspicion of sorcery. For Vivien Colera, meeting her will mark a new turning point in his life—and at the same time the revival of old secrets that intertwine several mysterious fates.